The invention relates to a method of manufacturing a low-pressure mercury vapor discharge lamp, in which method a closed holder containing a required quantity of mercury is placed in a radiation-transmitting discharge vessel, whereupon the discharge vessel is provided with a rare gas and is closed. Means for maintaining an electric discharge are arranged in or adjacent the discharge vessel, and the holder is opened after the discharge vessel has been closed.
The invention also relates to a holder containing mercury for use in a low-pressure mercury vapor discharge lamp manufactured by the above method.
The invention further relates to a low-pressure mercury vapor discharge lamp manufactured by means of this method.
A method of manufacturing a low-pressure mercury vapor discharge lamp of the kind mentioned in the first paragraph is known from U.S. Pat. No. 5,917,276. In the known method, a capsule or holder containing mercury and manufactured from glass is placed in a low-pressure mercury vapor discharge lamp, and the capsule or holder is opened in that it is locally heated through a wall portion of the discharge vessel by means of a radiation source.
The aim to reduce the quantity of mercury in the lamp, for example in counteracting that mercury is bound to lamp components in the discharge vessel during lamp operation and is thus no longer available for lamp operation, renders it desirable to use different mercury doses in dependence on the type and size of the low-pressure mercury vapor discharge lamp. A consequence of this is that the holders containing mercury will contain varying mercury doses for different lamp types.